1. Field of the Invention
The invention relates to remote management and analysis techniques for networks. More particularly, the invention relates to such techniques for local area networks constructed from home telephone wiring.
2. Background
Home Networking is a new segment of the networking marketplace that is poised for rapid growth. It is extremely important to consider that the emerging “in-home” networking technology is being targeted as a consumer grade service. As such any design goals must consider the “technology challenged” consumer and requires “out of the box” functionality. In the case of “in-home” networking via the existing telephone cable (HPN) the expectation from the consumer simply is that the technology functions properly and requires little more than installing a (provided) cable into an available telephone jack in the home. Further, it is expected that the technology provides a path to install the upper level protocols and drivers with no network configuration required by the consumer. This model obviously assumes that no “truck roll” occurs, and that there is no need for a qualified service personnel to come into the home.
Success in the consumer market requires that a home networking technology be inexpensive, easy to install, and easy to use. To be truly effective and embraced by consumers, a home networking solution must meet these criteria:                No new wiring must be needed. Most existing homes are not wired for traditional networking equipment        It must be simple to install and use        It must be low cost to allow the mass market to enjoy the benefits of home networking        It must have adequate range to operate within a typical home        It must support high speed data rates        The networking capability must grow with user applications without rendering existing devices obsolete        The network must be secure. The network data must remain private; it must not be accessible to neighbors or anyone outside the home.        
To achieve these goals the ability to offer robust products under extremely challenging “in-home” wiring topologies is absolutely critical.
The Home Phoneline Networking Alliance (“HomePNA™”) 1.0 and 2.0 specifications use a PSD mask that extends from 4 to 10 MHz. HPN signals are imposed on the existing telephone wiring inside a dwelling or office, and are used for local communication between HPN stations. The same inside telephone wiring may simultaneously carry POTS, ISDN or ADSL services since the HPNA signals occupy spectrum that is higher in frequency than any of those services. Assume a system sharing the phoneline media in a Frequency Division Multiplexed (FDM) topology as shown in FIG. 1. In this arrangement Plain Old Telephone Service (POTS) exists in the 0-4 kHz region, the xDSL service is present from 25 kHz to approximately 1.1 MHz (depending on the definition of “x”), and the HPN spectrum occupies 5.5-9.5 MHz for HomePNA Version 1.x technology and 4.75-9.25 MHz for HomePNA Version 2 technology. The spectral allocation for the VDSL services is not yet established but it is expected to use the 26 kHz to 10 MHz region.
This advantage is important because it is anticipated that due to the cost effectiveness of HPN solutions multiple devices in consumer space will become linked to desired high speed home networked devices and computers for the purposes of automation and data sharing.
Several factors need to be considered when investigating the design challenges of networking within the home environment over the existing copper plant. These challenges include exploring the areas of the “in-premises” wiring environment, understanding the telephone wiring topologies used in “typical” homes, modeling the interference and channel impairments in the existing copper plant, and understanding the spectral compatibility issues of sharing the media with existing services such as telephones, answering machines, baseband modems, and emerging high speed digital modems (xDSL).
Home phoneline networking presents the following challenges:                Must tolerate completely random and unspecified wiring topologies. The telephone wiring structure within each home is unknown and even changes on a day to day basis. For example, a simple action like plugging in a telephone or fax machine will add a branch onto the phoneline wiring tree.        Must be designed to take into consideration the unknown but typically large degree of signal attenuation which occurs within the random tree network topology A transmitted pulse is attenuated and scattered on the wires as it traverses the wiring. The longer the pulse travels through the wire, the more the signal is attenuated. This effect is compounded by impedance mismatches and lack of termination.        Must be able to tolerate high and varying levels of signal noise. Appliances, heaters, air conditioners, consumer appliances, and telephones all add random and varying levels of signal noise onto the phone wires.        Must be able to tolerate the dynamically changing transmission line characteristics. Telephones and other phoneline devices have a wide range of dynamically changing operating characteristics which, if the network is not properly designed, can interfere with data transmission. The simple act of a user picking up a telephone can dramatically change the data transmission characteristics of the phone wiring. Conversely, without care, data transmissions might interfere with the proper operation of telephones and fax machines.        Must he able to coexist with telephone service and comply with regulatory initiatives such as FCC Parts 15 and 68. Phoneline network solutions are constrained to use signals with low energy levels, which further complicates the task of establishing adequate signal-to-noise ratios.        And, finally, must maximize data throughput given the above constraints and limitations.        
Achieving the goals needed to make home networking a success is clearly a challenging task. Various environmental factors lead to potential compromising of robustness and sacrificing data throughput of “in-home” networks. The harsh environment does not leave room for compromising the robustness of home networking technology if a trouble-free consumer experience is desired.
The home networking market growth will depend on the emergence of high-speed broadband access as a catalyst as well as availability of robust, low cost, easy to install standardized home networking equipment. Technical analysis has demonstrated that there is little system margin available for achieving the desired rates and robustness if a trouble-free consumer experience is desired.
In a consumer-grade service offering, such as the Home Networking market, it must be assumed that the consumer neither understands nor has the capability to diagnose and remediate problems in networking systems. When problems do arise the consumer typically places a call to a call-center where a “qualified” attendant is available to assist in problem diagnosis and remediation. This is a costly model and minimizing the call-center time is absolutely critical. To properly accomplish this task the call-center attendant often needs to gain insight into the consumer system.
User applications that allow information on a per vendor/Network Interface Card (NIC) basis are generally available but on a very limited basis. However, these interface application programs are not consistent and will not operate with other vendor offerings that may be on the network. Further, these tools to date have been provided for on-site network management personnel that are skilled in the art of network management. Residential applications, however, are consumer focused. Generally, these consumers have little or no prior network management experience. Further, the design challenges of networking within the home environment over the existing copper plant present new issues that to date have not been encountered nor considered by the industry.